Move classes not related to mining to io package

1 files changed, 92 insertions, 0 deletions

diff --git a/src/io/BearerRequester.java b/src/io/BearerRequester.java
new file mode 100644
index 0000000..4cb554b
--- /dev/null
+++ b/src/io/BearerRequester.java
@@ -0,0 +1,92 @@
+package io;
+
+import java.io.IOException;
+import java.net.HttpURLConnection;
+import java.net.URL;
+import java.net.URLConnection;
+import org.apache.commons.io.Charsets;
+import org.json.JSONException;
+import org.json.JSONObject;
+import support.ConsumerKeySecret;
+
+/**
+ * An API requester used for application-only requests. Not all requests are
+ * allowed, see https://dev.twitter.com/docs/auth/application-only-auth for
+ * details.
+ *
+ * @author Peter Wu
+ */
+public class BearerRequester extends AbstractRequester {
+
+    /**
+     * A base64-encoded access token that authenticates requests.
+     */
+    private final String access_token;
+
+    /**
+     * Instantiates a requester with the given access token. The caller should
+     * test the token for validity.
+     *
+     * @param access_token The bearer token that authenticates a request.
+     */
+    public BearerRequester(String access_token) {
+        this.access_token = access_token;
+    }
+
+    /**
+     * Instantiates an instance, requesting an access token from the provided
+     * consumer key and secret.
+     *
+     * @param secrets The consumer secrets provided by Twitter.
+     * @throws IOException if a failure occurred while acquiring a token.
+     */
+    public BearerRequester(ConsumerKeySecret secrets)
+            throws IOException {
+        String postData = "grant_type=client_credentials";
+        URL url = buildUrl("oauth2/token");
+        HttpURLConnection conn = open(url);
+        conn.setRequestMethod("POST");
+        // set request headers
+        conn.addRequestProperty("Authorization", "Basic "
+                + secrets.getBearerTokenBase64());
+        conn.addRequestProperty("Content-Type",
+                "application/x-www-form-urlencoded; charset=UTF-8");
+        conn.setFixedLengthStreamingMode(postData.length());
+        // connect and send request
+        conn.setDoOutput(true);
+        conn.getOutputStream().write(postData.getBytes(Charsets.UTF_8));
+
+        try {
+            JSONObject resp = getResponseAsJson(conn);
+            // TODO: parse resp.errors
+            if (!resp.getString("token_type").equals("bearer")) {
+                throw new IOException("Expected bearer token type");
+            }
+            access_token = resp.getString("access_token");
+        } catch (JSONException ex) {
+            // treat JSON errors as if an I/O error occurred
+            throw new IOException(ex);
+        }
+    }
+
+    @Override
+    protected void preconnect(URLConnection conn) throws IOException {
+        // requests do not have to be signed, instead rely on the Bearer token
+        conn.addRequestProperty("Authorization", "Bearer " + access_token);
+    }
+
+    /**
+     * @return the access token that authenticates requests.
+     */
+    public String getAccessToken() {
+        return access_token;
+    }
+
+    @Override
+    public boolean isValid() throws IOException {
+        // NOTE: this actually contributes to the ratelimit (12/minute)
+        // TODO: find alternative that does not hit the ratelimit
+        JSONObject obj = getJSONRelax("application/rate_limit_status");
+        return !obj.has("errors");
+    }
+}